TY - JOUR
T1 - A Conducting Salt-Based Amperometric for Measurement of Extracellular Lactate Accumulation in Ischemic Myocardium
AU - Marzouk, Sayed A.M.
AU - Cosofret, Vasile V.
AU - Buck, Richard P.
AU - Yang, Hua
AU - Cascio, Wayne E.
AU - Hassan, Saad S.M.
PY - 1997/7/15
Y1 - 1997/7/15
N2 - In this paper, fabrication, characterization, and physiological application of a miniaturized amperometric lactate biosensor are described. The sensor is based on cross-linked lactate oxidase and tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) charge transfer complex. The sensor was developed for continuous quantitative measurement of the lactate accumulation in ischemic myocardium under severe depletion of oxygen. The sensor was evaluated in vitro at an applied potential of 0.15 V vs Ag/AgCl; it proved to combine all the performance characteristics desired for the present application, such as proper response in absence of oxygen, good operational stability, good accuracy and precision (103.5 ± 1.2%), adequate response time (t95% = 80 s), and wide linear dynamic range up to 27 mM (r = 0.9998) in N2-saturated solutions and at 37°C. The prepared sensors (n = 12) showed sensitivity of 380 ± 90 nA/mM, and a background current of 240 ± 50 nA. The lower limit of detection is 0.4 ± 0.15 mM with a S/N ratio equal to 3. Results obtained for direct lactate monitoring in ischemic rabbit papillary muscle under no-flow conditions and PO2 <6 mm Hg are presented.
AB - In this paper, fabrication, characterization, and physiological application of a miniaturized amperometric lactate biosensor are described. The sensor is based on cross-linked lactate oxidase and tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) charge transfer complex. The sensor was developed for continuous quantitative measurement of the lactate accumulation in ischemic myocardium under severe depletion of oxygen. The sensor was evaluated in vitro at an applied potential of 0.15 V vs Ag/AgCl; it proved to combine all the performance characteristics desired for the present application, such as proper response in absence of oxygen, good operational stability, good accuracy and precision (103.5 ± 1.2%), adequate response time (t95% = 80 s), and wide linear dynamic range up to 27 mM (r = 0.9998) in N2-saturated solutions and at 37°C. The prepared sensors (n = 12) showed sensitivity of 380 ± 90 nA/mM, and a background current of 240 ± 50 nA. The lower limit of detection is 0.4 ± 0.15 mM with a S/N ratio equal to 3. Results obtained for direct lactate monitoring in ischemic rabbit papillary muscle under no-flow conditions and PO2 <6 mm Hg are presented.
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U2 - 10.1021/ac970020s
DO - 10.1021/ac970020s
M3 - Article
C2 - 9230678
AN - SCOPUS:0030787453
SN - 0003-2700
VL - 69
SP - 2646
EP - 2652
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 14
ER -